Bar holder arrangement for bar stock material to be fed to a machine tool

ABSTRACT

A bar holder arrangement for holding bar stock material to be fed to an automatic machine tool comprises a frame and an elongated bar holder mounted in the frame. The bar holder includes an elongated member and a plurality of lever members which are mounted on the elongated member for pivotal movement between a gripping position and an open position, each lever member has at least one upstanding gripping member disposed on at least one end thereof. The lever members are pivotally disposed at different locations with respect to each other along the elongated member so that an upstanding gripping member of one lever member cooperates with an upstanding gripping member located at the end of the next adjacent lever member. Means are provided for pivoting the lever members between the gripping position and the open position. When the lever members are in the open position, a length of bar stock material may be dropped into the bar holder. The lever members are then pivoted to the gripping position so that the upstanding gripping members define a receiving means which holds the length of bar stock material in place. The arrangement may include a plurality of bar holders mounted in a reel formed by multi-armed spiders and a plurality of elongated members. The reel is rotatably mounted in the frame structure.

United States Patent [1 1 Doe 11] 3,802,689 Apr. 9, 1974 BAR HOLDER ARRANGEMENT FOR BAR STOCK MATERIAL TO BE FED TO A MACHINE TOOL [75] Inventor: Ewart Harold Doe, Houghton near Stockbridge, England [73] Assignee: Twyford Moors (Aircraft &

Engineering) Limited, Eastleigh, Hampshire. England 22 Filed: Oct.l2, 1971 21 Appl. No.: 187,985

[30] Foreign Application Priority Data Oct. 22, 1970 Great Britain 50307/70 521 u.s.c|. 269/57, 29/200 P, s2/2.7,

[56] References Cited UNITED STATES PATENTS 1,611,738 12/1926 Guilford 269/58 X 2,855,815 10/1958 Miller 82/2.5 X 3,218,899 ll/l965 Everett 269/153 3,322,423 5/1967 Popow et a1. 269/274 3,385,138 5/1968 Wusteney et a1. 269/321 R 3,566,507 3/1971 Jacobsen 29/200 P 3,630,391 12/1971 Wilson 269/58 X FOREIGN PATENTS OR APPLICATIONS 818,009 8/1959 Great Britain 82/2.7

Primary Examiner-Al Lawrence Smith Assistant Examiner-J. T. Zartarga Attorney, Agent, or Firm-Marva & Smith [5 7] ABSTRACT A bar holder arrangement for holding bar stock mate rial to be fed to an automatic machine tool comprises a frame and an elongated bar holder mounted in the frame. The bar holder includes an elongated member and a plurality of lever members which are mounted on the elongated member for pivotal movement between a gripping position and an open position, each lever member has at least one upstanding gripping member disposed on at least one end thereof. The

lever members are pivotally disposed at different locations with respect to each other along the elongated member so that an upstanding gripping member of one lever member cooperates with an upstanding grip- 7 ping member located at the end of the next adjacent lever member. Means are provided for pivoting the lever members between the gripping position and the open position. When the lever members are in the open position, a length of bar stock material may be dropped into the bar holder. The lever members are then pivoted to the gripping position so that the upstanding gripping members'define a receiving means which holds the length of bar stock material in place.

The arrangement may include a plurality of bar holders mounted in a reel formed by multi-armed spiders and a plurality of elongated members. The reel is rotatably mounted in the frame structure.

11 Claims, 7 Drawing Figures PATENTED APR 9 SHEET 1 OF 4 BAR HOLDER ARRANGEMENT FOR BAR STOCK MATERIAL TO BE FED TO A MACHINE TOOL SUMMARY OF THE INVENTION The invention relates to a bar holder arrangement for holding bar stock material to be fed to a machine tool. Such a machine tool may for example be an automatic multi-spindle lathe, a single spindle lathe or a centreless grinding machine.

According to the invention a bar holder arrangement for holding bar stock material to be fed to a machine tool comprises a frame and at least one elongated bar holder mounted in the frame. Each bar holder comprises a plurality of levers each pivotably mounted on an elongated member of the bar holder. Each lever has at one of its ends an upstanding member having a semicircular recess therein and at the otherof its ends a further upstanding member having a semi-circular recess therein. The levers are so disposed along the elongated member that said upstanding member of one lever cooperates with said further upstanding member of the next adjacent lever to define a circular receiving means for a length of bar stock material. Means are provided for pivoting said levers to separate the upstanding member of each lever from the further upstanding member of an adjacent one of the levers to open the bar holder and enable a length of bar stock material to be moved to a position in which it is received by said circular receiving means when the levers are moved to respective positions in which the upstanding member of each of thelevers abuts the further upstanding member of an adjacent one of the levers to form said circular receiving means.

Where a plurality of bar holders are required they are advantageously mounted in a reel, for example containing six bar holders, which is rotatable in the frame. The elongated members are advantageously secured in relative positions by means of a plurality of spiders, each spider having a number of arms equal to the number of bar holders on the reel. Means are provided to couple the spider, at the end of the reel to be adjacent the machine tool to which barstock is to be fed, to the machine tool so that the reel rotates with the machining head of the machine tool as the machining head is indexed around.

The semi-circular recesses in the upstanding member and the further upstanding member of each of the levers are advantageously provided by inserts received in said upstanding member and said further upstanding member, the inserts advantageously being of a plastics material such as nylon and each being secured insaid upstanding member or said further upstanding member by means of generally U-shaped members of a resilient material, the arms of the U-shaped member extending through aligned apertures in the inserts and in said upstanding members and said further upstanding members respectively. The inserts are readily replaceable to permit changes in diameter of bar stock material to be fed and the machine is advantageously provided with a set of a sufficient number of inserts for each diameter of bar stock likely-to be used between a quarter-inch diameter and one and three-quarters inch diameter.

Each of the levers is of generally Z or reverse 2- shape, that is to say it has three integral arms, a first arm carrying said upstanding member at its outer end and at its inner end being coupled to a second arm substantially at right angles thereto, and the second arm at its other end being coupled to the inner end of a third arm which at its outer end bears said further upstanding member. Each lever is pivotally mounted on one of the elongated members of the reel at the junction of its first and second arms and at the junction of its second and third arms is coupled to an actuator bar which extends parallel to its respective elongated member. Longitudinal displacement of the actuator bar is effective to cause the levers coupled thereto to pivot about their pivots on the elongated member to move said upstanding members and said further upstanding members outwardly from a center line of the bar holder to permit a length of bar stock material to be dropped into the bar holder.

A bottom stop, onto which a length of bar stock material to be held by the bar holder can be dropped, advantageously comprises a U-shaped member with an insert of a resilient material, such as nylon, in the lower end thereof, the U-shaped member being adjustable in height and being mounted on the elongated member aligned with the centre line of the bar holder.

Means for moving the actuator bar to open the re spective bar holders when so desired, and for securing the actuator bar against movement when such movement is not desired, may comprise a bifurcated member carried by each actuator bar at the end of the reel remote from the machine tool to which bar stock material is to be fed, the bifurcated member cooperating with opposite faces of a flange of a circular track as the reel is indexed and the flange having a gap therein such that at one position only of each actuator bar as it is indexed round with the reel, each actuator barcan be moved longitudinally. Said means for moving the actuator bar further comprise a pivotally mounted lever which in a first position prevents longitudinal movement of an actuator bar having its bifurcated member aligned with said gap in the flange of the circular track, said pivotally mounted lever being movable by a ram from said first position to a second position and entraining for moving therewith an actuator bar having its bifurcated member aligned with said gap in the flange of the circular track to cause that actuator bar to open the respective bar holder.

BRIEF DESCRIPTION OF DRAWINGS The invention is diagrammatically illustrated by way of example in the accompanying drawings, in which:

FIG. 1 is a plan view of part of a bar holder for a bar holder arrangement according to the invention;

FIG. 2 is a side view partly in section of one lever of the bar holder of FIG. 1. showing at the right-hand end thereof a nylon insert and a U-shaped member for retaining said insert;

FIG. 3 is an end view of a spider for a reel to support a plurality of the bar holders of FIG. 1;

FIG. 4 is a sectional view taken on line IV-IV of FIG. 3 and showing the mounting of a spider in the frame of the bar holder arrangement;

FIG. 5 is a rear end view of a bar holder arrangement according to the invention including a reel mounting a plurality of the bar holders shown in FIG. 1;

FIG. 6 is a view in the direction of arrow VI of FIG. 5; FIG. 7 is a view in the direction of arrow VII of FIG. 2.

DESCRIPTION OF SPECIFIC EMBODIMENTS Lengths of bar stock material (not shown) but supported on a face 103a of the slot 103 can be fed one at a time under the control of a feed mechanism, part of which is generally indicated at 105, through the vertical slot 104 into bar holders 106 (FIG. 1). Six bar holders 106 may be mounted on the reel mounted for rotation in the circular aperture 102 of the frame member 100.

The reel is formed by four spiders 107 (FIG. 3) aligned respectively with the four frame members 100, each of the spiders 107 having six arms I08 and the respective arms of the four spiders 107 being secured together by six longitudinally extending members 109, only one of which is shown in FIG. 3. To avoid the manufacturing difficulties of tapping holes in the arms 108 to receive bolts for securing the longitudinal members 109 to the arms 108, blocks 1 are bolted to the sides of the arms 108 by bolts passing through holes 111 in the arms 108 and the longitudinal members 109 are secured to the blocks 110 by bolts 112 engaging in holes tapped in the blocks 110 previous to fitting them to the arms 108.

As shown in FIG. 4, the spiders 107 are mounted for rotation in the circular apertures 102 of the frame members 100 by forming a slot 113 in the end of each of the arms 108 of'the spiders 107 and mounting a ball bearing 114 in each of the slots 113 by means of a pin 115 extending through an aperture 116 in the arm 108, the outer race of the bearing 114 bearing against the inner face of the circular aperture 102 of the frame member 100.

A central aperture 117 is provided in each of the spiders 107, the apertures 117 each including a keyway 118 whereby the spiders 107 can be keyed onto a longitudinally extending shaft to set up the spiders 107 in desired positions on assembly. The shaft received in the apertures 117 may be left in place after the reel has been assembled or may be removed and a similar but much shorter shaft be provided to extend from a front end spider 107 to an automatic machine tool fed by the bar holder arrangement whereby the reel is rotated as the machining head of the machine tool is indexed around.

Levers 95 (FIGS. 1 and 2) are pivotally mounted between a gripping position and an open position on the longitudinal members 109 of the reel by means of bolts 96 each of which pass through a respective boss 97 of its lever 95, the bore in the boss 97 through which the bolt 96 passes being provided with self-lubricating bushes 98. As is evident from the drawings, the lever members 95 are pivotally disposed at different locations with respect to each other along the elongated member 109. Each lever 95 comprises a first arm 95a, a second arm 95b and a third arm 950. At its outer end, the arm 95a has an upstanding gripping member 119, which, as shown in FIG. 7, is of generally semi-circular form and has a pair of small diameter longitudinally ex tending bores therein to receive the side pieces of a generally U-shaped spring pin 120. The spring pin 120 also passes through end flanges 121 of an insert formed as a nylon half bush 122 whereby the half bush 122 is secured to the upstanding portion 119.

At the outer end of the arm 950 of the lever 95, an upstanding gripping member 123 is provided which is similar to the upstanding gripping member 119 but is oppositely handed, that is to say the bore of the half bush 122 held in the upstanding member 123 faces in a direction I away from that of the half bush 122 of the upstanding member 119.

The lever is coupled to an actuator bar 125, extending parallel to and in the same plane as its cooperating longitudinal member 109, by means of a pin 124 secured in a bore in the actuator bar 125 and surrounded by a nylon bush 124a, the nylon bush engaging in a slot 124b in the face of the lever 95 lying against the actuator bar 125.

The actuator bar 125 is longitudinally reciprocable with respect to the longitudinally extending member 109. The half bush I22 mounted in an upstanding member 119 of a lever 95 cooperates with a half bush 122 in an upstanding member 123 of an adjacent lever 95 to form a closed circular bush in the closed gripping position of the bar holder 106 illustrated in FIG. 1. Movement of the actuator bar 125 from this gripping position in the direction of the arrow shown on the actuator bar 125 in FIG. 1, that is to say toward the rear of the bar holder arrangement, will move the upstanding members 119 and 123 of each of the levers 95 of the bar holder 106 in the directions indicated by arrows thereon. Such movement will separate each of the cooperating pairs of upstanding members 119 and 123 in like manner to the opening of a breech to leave a breech gap therebetween through which a length of bar stock material can be dropped under the control of the feed means shown in FIG. 5. The bar drops through the breech gap onto a bottom stop 126 carried between the arms 127 and 128 of a U-shaped member 129, the position of which stop 126 is vertically adjustable with respect to a member 130 secured to the longitudinal member 109.

When a length of bar stock material has been dropped therebetween the upstanding members 119 and 123 can be moved back into abutment by a reverse movement of the actuator bar to that indicated by the arrow thereon so that the length of bar stock material is held in the bore of the two cooperating half bushes 122 held by the respective pairs of cooperating gripping members 119 and 123.

The levers 95 are advantageously each about eight inches long and for a reel twelve feet in length, eighteen such levers will be required for each bar holder. The

lever 95 at the forward end of the bar holder does not have an arm 95c and the lever 95 adjacent the rear end of the bar holder does not have an arm 95a.

The joint line, between the abutting faces of the upstanding members 119 and 123 and the cooperating half bushes 122, may extend (as shown in full lines in FIG. 1) parallel to and aligned with the center line of the bar holder 106 when the bar holder is closed. Alternatively (as shown in dotted lines in FIG. 1) the joint line may lie at an angle to the center line of the bar holder when the bar holder is closed so that the faces of the upstanding members 119 and 123 and the half bushes 122 which abut in the closed position of the bar holder lie parallel to the center line of the bar holder when the bar holder is open.

The direction of rotation of the machining head of a machine tool. may be clockwise or counterclockwise. The bar holderarrangement shown in the drawings is designed for operation with a machine tool, the machining head of which rotates in a clockwise direction when viewed from the end of the machine tool to which the bar holder arrangement is coupled. Thus the reel of the bar holder arrangement will be rotated in a clockwise direction when viewed as in FIG. 5. In the arrangement shown, the actuator bars 125 are provided on the inside of their associated longitudinal members 109, that is to say nearer to the axis of rotation of the reel, and a pull towards the rear of the bar holder arrange ment applied to the actuator bars 125 is effective to open the breeches. By providing the actuator bars 125 to lie on the opposite side of their associated longitudinal members 109, that is to say further away from the axis of rotation of the reel than their associated longitudinal members, a pull towards the rear of the bar holder arrangement can be made effective to close the breeches.

As shown in FIGS. 5 and 6, on the rear frame memher 100 of the bar holder arrangement, that is to say the frame member 100 at the end remote from the machine tool to be fed with bar stock material, a sub-frame is provided comprising two side members 94 bolted to the frame member 100, a cross piece 92 joining the members 94, an upwardly extending arm formed by a member 93a secured to the cross piece 92 and a member 931: secured to the upper end of the member 930 the member 9317 mounting a pivot pin 93c.

Each longitudinal member 109 extends beyond the rear frame member 100 to a position adjacent the cross piece 92 but each actuator bar 125 finishes immediately beyond the rear frame member 100. An extension 125a is provided of each actuator bar 125 and is coupled thereto, in a manner to permit longitudinal adjustment, by blocks 13] and a screw threaded stem 132.

A guide block 133 is rigidly secured to the rear end of each longitudinal member 109 and each guide block 133 has a longitudinal extending groove therein formed i by downwardly projecting portions thereof to form a guide to constrain the extension 125a of the associated actuator bar 125 for longitudinal movement only. A sidewardly projecting portion 125b of the extension 125a has two downwardly extending portions 1256 which are spaced apart a determined distance in the direction longitudinally of the machine and are formed of, or faced on their adjacent faces with, a low friction material such as Oilite." The two projections l25c lie against the two opposite faces of an outwardly extending flange of a stationary circular track 67 secured to a hub rigidly mounted on the cross piece 92. As the reel of the bar holder arrangement is indexed around, the projections 125C move round the circular track 67 and prevent any longitudinal movement of the extension 125a and thus of the actuator bar 125. A gap 134 is provided in the top of the flange of the circular track 67 sufficient to permit passage therethrough of the forward one of the projections 125a. Thus the actuator bar 125 of each bar holder 106 can only be moved longitudinally to open the bar holder 106 when the bar holder' 106 has been indexed to a position in which it lies below the slot 104 in the frame member 100. If desired or found necessary, the circular track 67 may include more than one outwardly extending flange and more than two downwardly extending projections 1250 may be provided to permit reduction of the load per unit area applied by the projections 125a to the circular track 67.

A roller 135 is mounted on an upwardly extending pin secured to the rear end of the extension 125a. An arm 91 is pivotally mounted on the: pin 93c at one of its ends and at the other of the ends is connected to the piston of a ram 136 which has its cylinder connected to the frame member 100. A member 66 is secured to the arm 91 and has two downwardly depending projections 137, one abutting the rear face of the roller 135 and the other abutting the forward face. Thus, in the position of the arm 91, shown in FIG. 6, the roller 135, passing between the projections 137, prevents longitudinal movement of the extension 125a and thus of the actuator bar 125 during the time that the projections 125a of the extension 125a pass across the gap 134 in the flange of the track 67.

When it is desired to open one of the bar holders 106 when positioned below the vertical slot 104, and this may only occur after several complete revolutions of the reel, depending upon the amount of the bar stock being used up by each machining operation, the ram 136 is operated to pivot the arm 91 about the pin 930 in a clockwise direction, as viewed in FIG. 6, such movement of the arm 91 causing the forward downwardly extending projection 137 of the member 66 secured to the arm 91 to push the extension 125a and thus the actuator bar 125 rearwardly, the guide block 133 ensuring that such movement: is longitudinally of the bar holder. Once the bar holder 106 has been opened by the movement of the actuator bar 125, the feed mechanism can be operated to drop a length of bar stock material into the bar holder 106. The ram 136 can thus be re-operated to pivot the lever 91, in the counterclockwise direction as viewed in FIG. 6, to cause the rearward one of the projections 137 of the member 66 to bear upon the roller 135 and move the extension a and thus the actuator bar 125 longitudinally to close the respective bar holder 106.

The six bar holders 106 on the reel are constructed to be identical and can be opened in turn as desired by means of the ram 136 as they come in turn to the position in which they lie below the vertical slot 104. The longitudinal movement of the actuator bar 125 necessary to open the respective bar holder 106 is advantageously one inch and if desired springs may be provided between the front end spider 107 and each of the respective actuator bars 125 to assist return movement thereof to close the respective bar holder 106.

Except for such adjustment as may be necessary to the feedmechanism 105, the only adjustment necessary to the bar holder arrangement to accommodate a change in diameter of bar stock materialis replacement of the half bushes 122 by removal of the U-shaped spring members 120, substitution of half bushes 122 of a different size and insertion of the spring it can be provided of any convenient length. Twelve feet long is a convenient length since this is the normally used length of bar stock material. The bar holder arrangement can, however, readily be lengthened, for example to 18 feet, by removing the bar holder operating gear from the rear frame member 100, bolting on a further length of reel and bolting the bar holder operating gear to the new rear frame member. The longitudinal members 109 and the actuator bars 125 are in any event each advantageously provided in a plurality of short lengths and secured together.

Although the bar holder arrangement of the invention has been described for use for holding bar stock material it is of course to be understood that it can also be used to hold tube stock material or material in elongated form of any other kind which is to be supplied to a machine tool for machining of workpieces and/or cutting off to required lengths.

What is claimed is:

l. A bar holder arrangement comprising:

a. a frame and at least one elongated bar holder mounted in the frame,

b. the bar holder including an elongated member and a plurality of lever members which are mounted on the elongated member for pivotal movement between a gripping position and an open position,

c. each lever member having at least one upstanding gripping member disposed on at least one end thereof,

d. said lever members being pivotally disposed at different axial locations with respect to each other along said elongated member so that in the gripping position an upstanding gripping member of one lever member will abut an upstanding gripping member located on the end of the next adjacent lever member, and

e. means for pivoting said lever members between the gripping position and the open position.

2. A bar holder arrangement as defined in claim 1 wherein there is a plurality of elongated bar holder members and a reel is rotatably mounted in said frame,

said plurality of elongated bar holders being mounted on said rotatable reel.

3. A bar holder arrangement comprising:

a. a frame and an elongated bar holder mounted in the frame,

b. the bar holder comprising a plurality of levers and an elongated member on which said levers are each pivotably mounted,

c. each of said levers having at one of its ends an upstanding member formed to present a semi-circular recess and at the other of its ends a further upstanding member formed to present a semi-circular recess,

d. the levers being disposed at different axial locations with respect to each other along the elongated member so that said upstanding member of one lever will abut said further upstanding member of the next adjacent lever to define circular receiving means for a length of bar stock material, and

e. means for pivoting said levers to separate said upstanding member of each lever from said further upstanding member of an adjacent one of said levers to open the bar holder and enable a length of bar stockmaterial to be moved to a position in which it is received by said circular receiving means when said levers are moved to respective positions in which said upstanding member of each of said levers abuts said further upstanding member of an adjacent one of said levers to form said circular receiving means.

4. A bar holder arrangement as claimed in claim 1, wherein each of said levers is of generally Z-shape and has three integral arms a first of said arms carrying said upstanding member at its outer end and at its inner end being coupled to one end of a second of said arms substantially at right angles thereto, and the second of said arms at its other end being coupled to the inner end of a third of said arms, which third of said arms at its outer end bears said further upstanding member.

10 5. A bar holder arrangement comprising:

a. a frame and an elongated bar holder mounted in the frame,

b. the bar holder comprising a plurality of levers and an elongated member on which said levers are each pivotably mounted,

6. each of said levers having at one of its ends an upstanding member formed to present a semi-circular recess and at the other of its ends a further upstanding member formed to present a semi-circular recess,

d. each said lever is of generally Z-shape and has three integral arms,

e. a first of said arms carrying said upstanding member at its outer end and at its inner end being coupled to one end of a second of said arms substantially at right angles thereto,

f. the second of said arms at its other end being coupled to the inner end of a third of said arms,

g. the third of said arms at its outer end bears said further upstanding member,

h. each said lever is pivotally mounted on said elongated member at the junction of said first of its arms and said second of its arms,

. the levers being so disposed along the elongated member that said upstanding member of one lever cooperates with said further upstanding member of the next adjacent lever to define circular receiving means for a length of bar stock material, and

j. means for pivoting said levers to separate said upstanding member of each lever from said further upstanding member of an adjacent one of said levers to open the bar holder and enable a length of bar stock material to be moved to a position in which it is received by said circular receiving means when said levers are moved to respective positions in which said upstanding member of each of said levers abuts said further upstanding member of an adjacent one of said levers to form said circular receiving means,

k. said pivoting means including an actuator bar which extends parallel to said elongated member,

. each of said levers being coupled to said actuator bar at the junction of said second of its arms and said third of its arms and in a manner such that longitudinal displacement of the actuator bar is effective to cause said levers coupled thereto to pivot about their pivots on said elongated member to move said upstanding members and said further upstanding members outwardly from a center line of the bar holder to permit a length of bar stock material to be dropped into the bar holder.

6. A bar holder arrangement as defined in claim 5 including a bottom stop onto which a length of bar stock material to be held by the bar holder can be dropped,

said bottom stop comprising a U-shaped member with an insert of a resilient material in the lower end thereof,

said U-shaped member being adjustable in height and being mounted on said elongated member aligned with the center line of the bar holder.

7-. A bar holder arrangement as defined in claim including a guide carried by said elongated member,

said guide constraining said actuator bar for longitudinal movement only.

8. A bar holder arrangement as defined in claim 5 wherein each of said levers is coupled to said actuator bar by means of aprojection from said actuator bar engaging in a slot located in the respective lever at the junction of said second of the arms and said third of the arms of said lever.

9. A bar holder arrangement comprising:

a. a frame and an reel rotatably mounted in said frame, j

b. aplurality of elongated bar holders disposed on said reel, g j i 'c. each said elongated bar holder comprising a plurality of levers and an elongated member on which said levers are each pivotably mounted,

d. each of said levers having at one of its ends an upstanding member formed to present a semi-circular recess and at the other of its ends a further upstanding member formed to present asemi-circular recess, i

e. each said lever is of generally Z-shape and has three integral arms,

f. a first of said arms carrying said upstanding member at its outer end and at its inner end being coupled to one end of a second of said arms substantially at right angles thereto,

the second of said arms at its other end being coupled to the inner end of athird of said arms,

. the third of said arms at its outer end bears said further upstanding member,

. each said lever is pivotally mounted on said elongated member at the junction of said first of its arms and said second of its arms,

j. the levers being so disposed along the elongated member that said upstanding member of one lever cooperates with said further upstanding member of the next adjacent lever to define circular receiving means for a length of bar stock material, and

k. means for pivoting said levers disposed on each of said elongated members to separate said upstanding member of each lever from said further upstanding member of an adjacent one of said levers H to open the bar holder and enable a length of bar it is received by said circular receiving means when said levers are moved to respective positions in which said upstanding member of each of said levers abuts sa'id further upstanding member of an adjacent one of said levers to form said circular receiving means, i

1. said pivoting means including a plurality of actuator bars corresponding in number to the plurality of elongated bar holders wherein each of the actuator bars extends parallel to said elongated member in each elongated bar holder,

in. said pivoting means further including actuating means for moving each said actuator bar longitudinally to open each bar holder when so desired and for securing said actuator bar against longitudinal movement when such movement is not desired,

n. said actuating means including a plurality of bifurcated members wherein a, respective bifurcated member is carried by said actuator bar,

0. said frame including a fixedcircular track having a flange with opposite faces,

p. said bifurcated members being disposed adjacent H said frame to cooperate with opposite faces of said flange of thecircular track as saidreel is indexed around,

q. said flange having a gap therein such that each actuator bar of each bar holder is movable longitudinally at one position only as it is indexed around with said reel. j i

10. A bar holder arrangement as defined in claim 9 wherein said actuating means includes a pivotally mounted lever which in a first position prevents longitudinal movement of that one of said actuator barswhich has its bifurcated member aligned with said gap in said flange of the circular track, said bar holder arrangement further including a ram,

posite sides thereof engaged said further bifur cated member.- 

1. A bar holder arrangement comprising: a. a frame and at least one elongated bar holder mounted in the frame, b. the bar holder including an elongated member and a plurality of lever members which are mounted on the elongated member for pivotal movement between a gripping position and an open position, c. each lever member having at least one upstanding gripping member disposed on at least one end thereof, d. said lever members being pivotally disposed at different axial locations with respect to each other along said elongated member so that in the gripping position an upstanding gripping member of one lever member will abut an upstanding gripping member located on the eNd of the next adjacent lever member, and e. means for pivoting said lever members between the gripping position and the open position.
 2. A bar holder arrangement as defined in claim 1 wherein there is a plurality of elongated bar holder members and a reel is rotatably mounted in said frame, said plurality of elongated bar holders being mounted on said rotatable reel.
 3. A bar holder arrangement comprising: a. a frame and an elongated bar holder mounted in the frame, b. the bar holder comprising a plurality of levers and an elongated member on which said levers are each pivotably mounted, c. each of said levers having at one of its ends an upstanding member formed to present a semi-circular recess and at the other of its ends a further upstanding member formed to present a semi-circular recess, d. the levers being disposed at different axial locations with respect to each other along the elongated member so that said upstanding member of one lever will abut said further upstanding member of the next adjacent lever to define circular receiving means for a length of bar stock material, and e. means for pivoting said levers to separate said upstanding member of each lever from said further upstanding member of an adjacent one of said levers to open the bar holder and enable a length of bar stock material to be moved to a position in which it is received by said circular receiving means when said levers are moved to respective positions in which said upstanding member of each of said levers abuts said further upstanding member of an adjacent one of said levers to form said circular receiving means.
 4. A bar holder arrangement as claimed in claim 1, wherein each of said levers is of generally Z-shape and has three integral arms a first of said arms carrying said upstanding member at its outer end and at its inner end being coupled to one end of a second of said arms substantially at right angles thereto, and the second of said arms at its other end being coupled to the inner end of a third of said arms, which third of said arms at its outer end bears said further upstanding member.
 5. A bar holder arrangement comprising: a. a frame and an elongated bar holder mounted in the frame, b. the bar holder comprising a plurality of levers and an elongated member on which said levers are each pivotably mounted, c. each of said levers having at one of its ends an upstanding member formed to present a semi-circular recess and at the other of its ends a further upstanding member formed to present a semi-circular recess, d. each said lever is of generally Z-shape and has three integral arms, e. a first of said arms carrying said upstanding member at its outer end and at its inner end being coupled to one end of a second of said arms substantially at right angles thereto, f. the second of said arms at its other end being coupled to the inner end of a third of said arms, g. the third of said arms at its outer end bears said further upstanding member, h. each said lever is pivotally mounted on said elongated member at the junction of said first of its arms and said second of its arms, i. the levers being so disposed along the elongated member that said upstanding member of one lever cooperates with said further upstanding member of the next adjacent lever to define circular receiving means for a length of bar stock material, and j. means for pivoting said levers to separate said upstanding member of each lever from said further upstanding member of an adjacent one of said levers to open the bar holder and enable a length of bar stock material to be moved to a position in which it is received by said circular receiving means when said levers are moved to respective positions in which said upstanding member of each of said levers abuts said further upstanding member of an adjacent one of said levers to form said circular receiving means, k. said pivoting means including an actuator Bar which extends parallel to said elongated member, l. each of said levers being coupled to said actuator bar at the junction of said second of its arms and said third of its arms and in a manner such that longitudinal displacement of the actuator bar is effective to cause said levers coupled thereto to pivot about their pivots on said elongated member to move said upstanding members and said further upstanding members outwardly from a center line of the bar holder to permit a length of bar stock material to be dropped into the bar holder.
 6. A bar holder arrangement as defined in claim 5 including a bottom stop onto which a length of bar stock material to be held by the bar holder can be dropped, said bottom stop comprising a U-shaped member with an insert of a resilient material in the lower end thereof, said U-shaped member being adjustable in height and being mounted on said elongated member aligned with the center line of the bar holder.
 7. A bar holder arrangement as defined in claim 5 including a guide carried by said elongated member, said guide constraining said actuator bar for longitudinal movement only.
 8. A bar holder arrangement as defined in claim 5 wherein each of said levers is coupled to said actuator bar by means of a projection from said actuator bar engaging in a slot located in the respective lever at the junction of said second of the arms and said third of the arms of said lever.
 9. A bar holder arrangement comprising: a. a frame and an reel rotatably mounted in said frame, b. a plurality of elongated bar holders disposed on said reel, c. each said elongated bar holder comprising a plurality of levers and an elongated member on which said levers are each pivotably mounted, d. each of said levers having at one of its ends an upstanding member formed to present a semi-circular recess and at the other of its ends a further upstanding member formed to present a semi-circular recess, e. each said lever is of generally Z-shape and has three integral arms, f. a first of said arms carrying said upstanding member at its outer end and at its inner end being coupled to one end of a second of said arms substantially at right angles thereto, g. the second of said arms at its other end being coupled to the inner end of a third of said arms, h. the third of said arms at its outer end bears said further upstanding member, i. each said lever is pivotally mounted on said elongated member at the junction of said first of its arms and said second of its arms, j. the levers being so disposed along the elongated member that said upstanding member of one lever cooperates with said further upstanding member of the next adjacent lever to define circular receiving means for a length of bar stock material, and k. means for pivoting said levers disposed on each of said elongated members to separate said upstanding member of each lever from said further upstanding member of an adjacent one of said levers to open the bar holder and enable a length of bar stock material to be moved to a position in which it is received by said circular receiving means when said levers are moved to respective positions in which said upstanding member of each of said levers abuts said further upstanding member of an adjacent one of said levers to form said circular receiving means,
 10. A bar holder arrangement as defined in claim 9 wherein said actuating means includes a pivotally mounted lever which in a first position prevents longitudinal movement of that one of said actuator bars which has its bifurcated member aligned with said gap in said flange of the circular track, said bar holder arrangement further including a ram, said pivotally mounted lever being movable by said ram from said first position to a second position and entraining for movement therewith that one of said actuator bars that has its bifurcated member aligned with said gap in the flange of the circular track to cause said actuator bar to open the respective one of said bar holders.
 11. A bar holder arrangement as defined in claim 10 wherein said pivotally mounted lever carries a further bifurcated member, and each of said actuator bars carries a roller having opposite sides thereof engaged by said further bifurcated member. members
 120. This can be effected relatively quickly and without the need for any tools whereby the ''''down time'''' of the bar holder arrangement necessary to effect a changeover to a different size of bar stock material is considerably reduced having regard to previously proposed bar holder arrangements. The bar holder arrangement of the invention has the advantage that 